Since means for supplying hydrogen used as a fuel when a fuel cell system generates electric power has not been developed as a common raw material infrastructure, the fuel cell system normally includes a reformer which generates a hydrogen-containing gas from a city gas, a natural gas, a LPG, or the like supplied from the common raw material infrastructure.
The reformer causes a reaction of a raw material gas, such as the city gas, by using a reforming catalyst at a high temperature of about 600° C. to 700° C. to generate a hydrogen-containing gas containing hydrogen as a major component. In this case, the raw material gas contains a sulfur compound, and the sulfur compound needs to be removed since it is a poisoning material for the reforming catalyst. For example, the sulfur compound can be removed from the raw material gas by mixing a hydrogen gas and the raw material gas to cause hydrodesulfurization.
Here, proposed is a device configuration in which: a part of the hydrogen-containing gas generated by a reforming reaction of the reformer is returned to a raw material gas passage as the hydrogen for the hydrodesulfurization (hereinafter referred to as “recycling”); and a condenser is disposed on a recycle passage to suppress passage clogging of the recycle passage by condensed water (see PTL 1, for example).